Vehicle with means for laterally stabilizing tandem drive axles and transmitting brake and drive torque reactions to the frame



2,607,431 TANDEM DRIVE AXLES EACTIONS TO THE FRAME S TABILIZING AND-TRANSMITTING BRAKE AND DRIVE TORQUE R Filed Feb. 4, 1946 19, 1952 1.. R. BUCKENDAL'E VEHICLE WITH MEANS FOR LATERALLY 3 Sheets-Sheet 1 Lawrence RBubkenJa [e INVENTOR WWW n ATTORNEYS 1952 L R. BUCKENDALE 2,607,431

VEHICLEWITH MEANS FOR LATERALLY STABILIZING TANDEM DRIVE AXLES AND TRANSMITTING BRAKE AND DRIVE TORQUE REACTIONS TO THE FRAME Filed Feb. 4, 1946 5 Sheets-Sheet 2 i Si l n? ilum 84 INVENTOR gawr en ce/i. Buckendale,

ATTORN EYS Patented Aug. 19, 1952 UNITED/STATES rem" OFFICE Lawrence R- Buckendale, Detroit, Mich, assi'gnor to The Timken-Detroit Axle Company, Detroit, Mich., a corporation of Ohio Application February 4, 1946, Serial No. 645,384

This invention relates to motor vehicle drive axles and axle assemblies and more particularly to an improved tandem axle assembly for short coupled vehicles and improved drive axle construction. V v

The major object and purpose of the present invention is to provide certain important improvements which will-reliably function to increase the stability and general operating efficiency of a tandem axle assembly of the type disclosed in the Buckendale Patent No. 1,946,060, issued February 6, 1-934, when used in a short coupled vehicle such as a cabv over engine tractor.

t is of major importance in vehicles employing such tandem axle units to obtain maximum pay load capacitywith minimum overall length of the vehicla Usually the load is supported by conventional leaf springs-centrally pivoted on a transverse frame bolster and having their opposite ends fiexibly connected with the respective housings for the front and rear axles of the tandem unit upon whichthe vehicle load is equally distributed. Owing to the'increase in pay load capacity in vehicles of this type it has been found necessary to materially increase torque output and to provide stabilizing means for the tandem axle unit. For the latter purpose, cross connections are provided between the axle housing and, opposite sides of the vehicle frame which serve to neutralize the effect of excessive lateral stresses while retaining overall flexibility.

Further, since it is not permissible to increase the overall length of a. short coupled .vehicle such as a cab over engine tractor vehicle in proportion to the increase in load capacity, it is necessary to, provide a. tandem axleunit for such a short coupled vehicle which will satisfy the above requirements and yet retain sumcie'nt propeller shaft length to-prevent high angularity with its accompanying destructive stresses in the universal joint connections. This problem is especially difficul-t wherelarge double reduction drive axles are incorporated in the unit. By means of the invention to" be presently described, I have succeeded in solving these several problems.

From. the above, it will be understood that it is one of the. principalobjects of this invention to provide a tandem axle-assembly and drive means therefor which is practically adaptable for use in short coupled; large capacity-heavy duty vehicles. l

It is a more particular'obje'ct of this invention to provide a tandem axle assembly for vehicles ll-Claims (Cl. mil-22) of the above type together with improved drive means for transmitting and uniformly distributing the torque load to the several vehicle wheels and embodying multiple reduction gear assemblies so located and arranged that the overall length of the vehicle in which my novel tandem axle unit is incorporated will not be increased.

Another object of the invention is to provide an improved assembly of the differential gear carrier and power transfer reduction unit for each of the axles.

A further object of the invention resides in the provision of a very simply constructed planetary gear reduction at the wheel ends of the axles which may be easily and quickly assembled or disassembled.

It is another detail object of the invention to provide a simple and novel mounting for the planetary pinion carrier so that it may have limited radial floating movement between the sun gear on the axle shaft and the planetary orbit gear, in order to avoid destructive localized tooth stresses.

*A still further object of this invention is to provide each axle shaft at its outer; end with a sun gear and means to resiliently journal the shaft end and vyieldingly center the sun gear provided with one practical embodiment of my improved-tandem axle unit; v

Figure 2 is-a plan view of the axle unit illustrating the general arrangement of the differential carriers and the associated power transfer units and the lateral stabilizing connections between the vehicle frame and the axle housings; I

Figure 3 is a side'ele'vation partly in section illustrating the adapter means for assembling the differential drive shaft and power transfer reduction gearing on the differential carrier;

Figure 4 is a fragmentary rear elevation of one of the axle housings taken on the line 4.-4- of Fig. 2, partly in'section andillustrating the planetary gear reduction mechanism between one of the axle shafts and one of the dual tired road wheels;

Figure 5 is a detailed sectional view on an enlarged scale of the planetary reduction gearing shown in Figure 4; v

Figure 6 is an end elevation of the axle of Figure 5, with certain parts broken away and in section; and

Figure 7 is a detail horizontal sectional View taken substantially on the lines 1-! of Figure 6.

With further detailed reference to the drawings, the side rails I of the vehicle frame are provided at their forward ends with any improved mounting means for the motor or engine (not shown). This end of the vehicle frame is also suspended by conventional means upon the front driven axle I2. The operators cab I4 is located directly above the engine while I designates the main transmission and I1 an auxiliary transmission suitably mounted in the frame through which the power is transmitted from the engine to the axle shafts of the tandem axle assembly, generally indicated at 28.

The frame rails I0 are of the usual channel form having their webs vertically disposed and upper and lower flanges extending inwardly therefrom. To each of these rails a depending bracket 22 is riveted or otherwise rigidly secured. Below the frame rails, the opposite ends of a transverse'frame bolster 24 are secured in the brackets'22 and upon the ends of this bolster longitudinally extending laminated leaf springs 26 are suitably pivoted intermediate of their ends. The opposite ends of these body suspension springs are flexibly connected respectively to the front and rear tandem axle housings 36 and 3|. Each of these housings, at each side of its central portion is also connected with the brackets 22 by means of the longitudinally extending upper and lower parallel torque rods 28. The construction of the tandem axle unit and its parallelogram torquing arrangements as thus far described are substantially the same as that shown in the above identified Buckendale patent.

Each of the axles includes co-axial axle shafts one of which is indicated at 32 in Figures 3, 4 and 5, said shafts being operatively connected by conventional differential gearing; The difierentials are disposed within the enlarged central sections 34 of the housings 38 and 3I and are preferably interchangeable. Each axle at, its outer end isprovided with planetary reduction gearing for transmitting the driving torque to the individual vehicle wheels. These planetary reductions, generally indicated at 40, will be hereinafter more fully described.

The enlarged center section 34 of each axle housing is provided at the rear side thereof with a differential receiving opening 42 provided with a locating face for the attaching flange 44 of a differential mechanism carrier 46 which may be rigidly secured to the housing by the conventional studs or other means. Preferably, the locating face of opening 42 is disposed at a vertically oblique inclination, as seen in Figure 3 of the drawing. 7 r

The differential mechanism carriers 46 project rearwardly from the respective axle housings and upon the rear end of each carrier a transfer gear case is assembled. Since these transfer gear cases, generally indicated at 68 and M respectively in Figure 1, ar of identical construction, the following detail description of one will suffice for both.

As clearly shown in Figure 3 of the drawings,

- means of the screws or bolts 98.

4. the differential mechanism carrier 46 is provided at its rear end with the opening 68 to receive a cylindrical bearing receiving cage 64 integrally formed with the adapter member 62 having a large diameter flange 66 abutting the end of the carrier 46 and rigidly'secured thereto by means of the bolts 68. The housing structure 63 of the transfer gear case is provided in its front wall with an opening 65 covered by adapter member 66 to which it is rigidly secured by the stud bolts 61. The transfer case housing 63 extends vertically above the differential carrier 46 and, above the level of the axle housing, the opposite lateral walls thereof are provided with suitable bearing indicated at 10 and I2, in which a shaft 14 is journalled. Within the housing 63, a gear I6 is splined or otherwise secured to the shaft I4. The opposite ends of each shaft M are splined as shown at 18 and 88 to receive universal joint connections between the two transfer units and the auxiliary propeller shaft 2| and between transfer unit 66 and the propeller shaft I9- connected with the output shaft of the auxiliary transmission IT. The rear end of shaft I4 of the transfer unit 6I may be capped as indicated at 84 in Figure 1.

Suitable bearings 86 are mounted in the cylindrical cage portion 64 of the adapter member 62, in which a shaft 88 for differential drive pinion 81 is journalled. Within the housing 63, a gear 96 is keyed or otherwise secured to shaft 88 and i in constant mesh with gear I6. Gear 98 is larger than gear 16 so as to provide a first drive speed reduction. The second speed reduction is provided between gear 81 and the differential ring gear (not shown). The rear wall of housing 63 is provided with opening 96 to receive a cage member 94 which also serves as a closure for said opening and is provided with an attaching flange secured to the housing wall by screws or studs 98. This cage member carries bearing 92 in which the rear end of the pinion shaft 88 is journalled. It will be noted that the cage member 94 is in clearance relation to the wall of opening 96 and is secured in place solely by This insures a proper alignment of the bearings 86 and 9.2 and obviates a possible eccentric relation thereof due to the mounting of the gear housing upon the adapter member 62. Propeller shafts I9 and 2| and shafts I4 and 88 all have their axes in a common vertical plane on the horizontal centerline of the vehicle in the preferred embodiment.

The central portion 34 of each axle housing is provided at the forward side thereof with a boss I located substantially on the vehicle center line. In this boss, a vertical pivot pin I02 is suitably fixed and has a lever I84 journalled thereon intermediate of its ends. To each end of this lever, the inner end of atransverse rod I86 and I08 respectively is universally pivoted. The outer end of each rod is similarly universally pivoted as indicated at I II] to one of the vehicle frame side rails I6. With this arrangement, when the vehicle frame II] shifts laterally with respect to the axles, the reaction of one of the rods I66 or I08 which is in compression tends, through the equalizing lever I64, to neutralize the reaction of the other rod. By the provision of the universal connection between these rods and each axle housing, the vehicle frame may have a transverse tilting or rocking motion, one side thereof rising while the-other sid lowers, without imposing undue stress upon the outer ends of the respective axle shafts and the vehicle wheels associated therewith. This planetary reduction will now be more particularly described with reference to Figures 4 7 of the drawings.

Each axle housing is provided at "s opposite ends with external tapered splines I33 engaged by internal splines I32 on a mounting ring I34 for the planetary pinion carrier. Ring I34 is forced onto splines I33 and secured against outward axial movement with respect to the hous-' ing by means of the lock nut assembly I33 threaded upon the end of the housing. Ring I34 is also provided with external teeth or splines I36 engaged by mating internal splines I43 provided upon one annular side of member I36 of the planetary pinion carrier. There is suincient clearance between the mating teeth I36 and I43 to permit a slight radial floating movement of the planetary pinion carrier with respect to the ring I34 and the axle housing, while effectively preventing rotative movement of the carrier relative to said ring.

The planetary pinion carrier also includes spacing rings MI and I43 which are provided with circumferentially spaced apertured bosses I45 and I4! held in abutting contact by the connecting bolts I39, as shown in Figure 7, and thereby spacing said rings apart. These rings and the side member I38 are provided with registering apertures, in which the pinion shafts M2 have a driving fit or are secured by other conventional means, it being noted that ring I43 is in abutting engagement with the side face of the adjacent carrier member I38.

On each of the shafts I42, a planetary pinion I44 is journalled for free rotation between the rings I4! and I43 on the needle bearings indicated at I49.

On the axle housing between the ring I34 and brake mechanism indicated at I46, a dual tired wheel hub I48 is journalled by means of bearings I5I. This hub is provided with spaced radially extending flanges I50 and I52 respectively carrying the rims I53 upon which the wheel tires I54 and I56 are mounted in the usual manner. To the outer side of hub flange I56 a cylindrical housing wall I52 for the planetary gearing is secured by means of suitable. bolts and nuts indicated at I63. This housing wall rigidlycarries an internal annular orbit gear I34 which may be secured thereto by mating pressed fit, splines on said gear and housing wall, indicated at I66 or in any other desired manner. Between the inner end of the orbit gear I54 and an internal annular shoulder I63 on thehousingwall I62isinterplates I68 and I'll] overlap the orbit and plane'-' tary gears to prevent relative axial movement between the planetary pinions and the orbit gear and maintain the teeth of said gear'and pinions in full tooth contact. Preferably, the hub cap I14 is provided with an outer annular channel section I'IGreceiving thering I4I ofthepinion carrier and which renders the wall of the hub cap somewhat resilientlyyieldable' in the radial direction.v I 1 The outer end of each axle shaft 32 hasv a :sun gear I84 integrally formed therewith and provided with spur gear teeth I86 in constant mesh with the teeth of the planetary 'pinions 144;: Beyond the sun gean'thedxle shaftterminates in a diametrically reduced portion I82 journalled in a bearing I resiliently supported irr cage member I18 by means of theinterposed annular cushion of rubber or other resilient material indicated at Ill. The cage member eflflis' welded or otherwise rigidly secured; to. the inner' facej of the hub cap-I14. a

It will be evident from the abovedescription that in the transmission ofc'heavy drive torque from the axlev shafts to the wheels slight radial movement of the sun gear is 'permis'sible,"-and by the resilient mounting of the shaft end bearing I86 together with the radially resilient hub cap and the floating mounting of the pinioncarrier, the proper centered relation between the sun gear and the planetary pinions will be attained and maintained to insure; an equal distribution of the torque load between said pinions and avoid destructive localized tooth-pressures.

From the foregoing-description, the operation of the present invention may be readily understood. Thus, the driving force of therengine is delivered through primary transmission I5 and the short coupled propellershaft Ifito the auxiliary transmission II. Herethe power is divided, propeller shaft I6 delivering torqueto the front axles I2 while propeller shaft l l. delivers torque to the transfer gear case. 66;. .Here the torque is transmitted in a first speed reduction to the axle driving differential in housing 3.9. From shaft 14 of the transfer case 66, torque isalso delivered through propeller shaft 2| to transfer case 6 I' and transmitted at reduced speed to the axle shaft driving differential in the housing 3 I. From the axle shafts 32, the driving torque is finally trans-.

mitted at a further speed reduction to the respective vehicle wheels through the planetary driving gear units 40. j

It will be appreciated that the present invention provides a tandem :axle assembly and drive mechanism of short coupled heavy dut vehicles of high load capacity in; which maximum flexibility, and minimumoverall'length of the vehicle is obtained. At the same time there is sufficient propeller shaft length' to obviate the development of destruotivestresses inthe shaft connection in the relative vertical movement of the axle unit and the vehicle frame. In the unloaded conditionof the venue; the propeller shaft 2| is longitudinally-parallel with the vehicle frame while the propellenshaf t I9 extends upwardly at a very slight inclination fromthe transfer gear case 66 to the auxiliary transmission I7. By the provision ofthe adaptor members 62 for the power 'transfer ear'uhits'fid and 6|, the latter may quickly be assembled-with the differential gear carrier's oi disrnounted for changing the gear ratio or 'othe'r purposes. Also the several parts of the invention are of simple structural form and combined in a highly compact organization to provide an efliciently functioning tandem axle assembly and double reduction drive of this type.

In my novel vehicle the tandem axles are disposed far forwardly so as to obtain a short wheel base tractor or like vehicle, but I am enabled to use a long propeller shaft with consequent low universal joint; angularity particularly by reason of the rearwardly projecting disposition of carriers .46 on the tandem axles thereby also permitting the advantages of high torque and double reduction drive without demanding additional space- Thus the drive enters each tandem axle from the rear, or just opposite to the conventional arrangements. To my knowledge this is the first time such a novel arrangement has been incorporated into a tandem axle vehicle.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In an automotive vehicle, a frame, a dirigib-le front axle supportingthe front end of the frame, a tendem drive axle assembly comprising two closely spaced driveaxles beneath a rearwardly spaced portion of the frame, a spring suspension between said assembly and the frame pivotally connected to the frame so that said assembly may have pivotal movement relative to. said frame about a lateral axis substantially parallel to said axles, means independently of said spring suspension interconnecting said axles and said frame for transmitting brake and drive torque reactions to the frame and stabilizing said tandem axle assembly longitudinally of the vehicle, and

means structurally distinct from said suspension and said longitudinal stabilizing meansconnected between said tandem drive axle assembly and said frame for laterally stabilizing said tandem axle assembly during its relative movement with respect to said frame, said lateral stabilizing means comprising an equalizing lever intermediately pivoted about an axis normal. to the axle axis on each drive axle, generally transverse rods connecting the opposite ends of said lever to opposite sides of the frame and universal connections between the rod ends and the lever and frame respectively, said suspension and longitudinal and lateral stabilizing means cooperating to provide a vehicle having optimum flexibility and improved drive torque.

2. The combination defined in claim 1 wherein said longitudinal stabilizing means comprises, spaced transversely aligned pairs of torque rods extending longitudinally of the vehicle frame, the adjacent ends of said pairs'being pivotally mounted relative to said frame intermediate said axles and the opposite ends of the torque rods of each of said pairs being pivotally connected respectivelyto the forward and rearward ones of said drive axles. v

3. The combination defined in claim 1 wherein said spring suspension comprises a plurality of leaf springs extending longitudinally of said frame between said drive axles; said springs being flexibly connected to said drive axles at their ends and pivotally connected intermediate the ends of said spring to said frame.

A tandem drive axle assembly for motor vehicles having a frame, comprising spaced axle housings having enlarged differential mechanism receiving portions provided with openings, differential mechanism and differentially driven axle shafts in said housings, road wheels journalled on the outer ends of each housing and drivingly connected with the respective axle shafts, a differential mechanism carrier demountably secured to the differential receiving portion of each axle housing over the associated opening, said carrier projecting from said housing and having an opening, a separate power transfer gear reduction unit for each diiferential mechanism carrier comprising a casing, a wall on said casing interfitting with said nose and serving as an adapter for demountably supporting each unit upon the respective gear carrier, each of said units including a power input shaft and a pinion shaft driven from the input shaft and connected to drive the associated differential, a propeller shaft drivingly connecting said input shafts, a suspension connecting the axle housings with each other and mounting the assembly on said vehicle frame and'maintaining said axles in longitudinal spaced relation, and means between each axle and said frame for laterally stabilizing said assembly comprising an equalizing lever pivoted intermediate its ends upon an axis normal to the axle axis on each drive axle housing, generally transverse rods connecting the opposite ends of said lever to opposite sides of the frame and universal connections between the rod ends and the lever and frame respectively.

LAWRENCE R. BUCKENDALE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,605,065 Rackham NOV. 2, 1926 2,064,262 Keese Dec. 15, 1936 2,144,359 Bryan Jan. 17, 1939 2,206,752 Price July 2, 1940 2,290,620 Brown July 21, 1942 2,291,174 Stewart July 28, 1942 2,306,856 Ash Dec. 29, 1942 2,309,162 Buckendale Jan. 26, 1943 2,347,987 Brumbaugh May 2, 1944 2,356,180 Roos Aug. 22, 1944 2,381,624 Simonds Aug. 7, 1945 2,386,917 Thornton Oct. 16, 1945 2,389,339 Ash Nov. 20, 1945 2,477,925 Gentry Aug. 2, 1949 FOREIGN PATENTS Number Country Date 301,584 Great Britain Dec. 6, 1928 389,900 Great Britain Mar. 30, 1933 

